[intractable]

The article brings to mind this wonderful short story by Ray Bradbury, "Pedestrian" [1]

    "What are you doing out?"
    "Walking," said Leonard Mead.
    "Walking!"
    "Just walking," he said simply, but his face felt cold.
    "Walking, just walking, walking?"
    "Yes, sir."
    "Walking where? For what?"
    "Walking for air. Walking to see."

[1] http://mikejmoran.typepad.com/files/pedestrian-by-bradbury-1...